Sorry, Ray. I tried to keep the term "bit number" out of the discussions because Lenz/Bachmann number the bits from 1 to 8 while the rest of the world number them from 0 to 7. Just to make matters worse, the wacky wizards number the bits from right to left even though just about everything else in the world is numbered from left to right. Strange people, these electronics geeks and computer nerds. And I are one of them.

Okay, I have given my head a good shake, and the bit numbers and binary values are temporarily gone. So how do we figure out what we need to put into CV 29 to make the decoder do what we want it to do? The easiest way is to refer to a look up table such as the one on page 34 at this link:

http://www.digitrax.com/ftp/Decoder_Manual.pdf There are five things you have to decide:

(1) do you want to use 14 speed steps or 28/128 speed steps?

(2) do you want to use a speed table?

(3) do you want analog mode (dc) turned on or off?

(4) which way do you want to operate the locomotive, forward or reverse?

(5) do you want to use a 2 digit or a 4 digit address?

The number you put into CV29 depends on all five of these things. Depending on which combination of these things you want, the number you put into CV29 can be any one of 32 possible numbers. Sixteen of these numbers will turn dc mode on. The other 16 numbers will turn dc mode off. You find the number you have to put into CV29 by looking in the left column next to the combination of things you want. (Ignore the numbers with an X in front of them.)

A very common combination is 18/128 speed steps, no speed table, dc mode on, forward operation and 2 digit address. Looking at the chart, this gives 006. So to get that combination, you put a 6 into CV29.

An equally common combination is 18/128 speed steps, no speed table, dc mode on, forward operation and

**4** digit address. Again looking at the chart, this combination gives 038. So we would put 38 into CV29.

It does not matter what brand of decoders you are using, that chart still works.

The bottom line is that there is no one number that you put into CV29 to turn dc mode on. But 6 and 38 are probably the most common, the difference between them being whether you want to use a 2 digit address or a 4 digit address. If the locomotive were a diesel that you wanted to run backwards in a consist, the corresponding numbers would be 7 and 39. The four numbers, 6, 38, 7 and 39 will cover 90% of the cases where you want dc mode turned on.

Jim (now gathering up those bits, bytes and geeky numbers that are scattered about the room.)